In electrical or electronic systems, various individual system modules, for instance various electronic/electric assemblies, various electronic/electric components, for instance various semiconductor components such as integrated circuits, etc., various sub-components, provided in one and the same component or integrated circuit etc., communicate via a transfer medium such as a bus system.
A bus system may comprise one or more transfer lines. Bus systems can be used jointly by several, in particular by two or more than two modules/components/elements of a respective system.
Many conventional bus systems comprise several partial systems, for example a data bus—consisting of one or more data lines—and/or an address bus—consisting of one or more address lines—and/or a control bus—consisting of one or more control lines—etc.
In comparison to this, other bus systems are of a much simpler construction. For example, a so-called IBCB bus (IBCB=Inter Block Communication Bus) in general merely comprises two transmission lines to connect two respective modules/components/elements.
Further examples for relatively simple bus systems are LIN busses (LIN=Local Interconnect Network), which generally comprise only one single transmission line, and CAN busses (CAN=Controller Area Network), which generally only comprise two or three lines (e.g., CAN_HIGH, CAN_LOW, and—optionally—CAN_GND (ground)), etc.
According to the CAN protocol, e.g., the CAN 2.0 protocol, each data frame transmitted via a CAN bus comprises a plurality of predefined fields (e.g., as defined in the “Base frame format”), e.g., a “start of frame” field, an “ID” field, a “DLC (Data length code)” field, followed by a “Data” field (containing the actual useful data to be transmitted), a “CRC (Cyclic redundancy checksum)” field, etc., and an “EOF (End of frame)” field.
Further, according to the CAN protocol, the data contained in the frames is transmitted at a predefined data rate, e.g., 1 Mbit/s in the case of a Highspeed bus, and, e.g., 125 kbit/s in the case of a Lowspeed bus.
To further enhance the data rate, the so-called CAN FD (CAN flexible data rate) protocol was defined.
According to the CAN FD protocol, the data contained in the “Data” field of a CAN frame (i.e., the actual useful data)—but not the data contained in the other fields of a CAN frame—is transmitted at a higher transmission rate, than prescribed in the CAN 2.0 protocol.
However, due to the above different data rates, CAN FD protocol modules/components/elements in general are not compatible with CAN 2.0 protocol modules/components/elements. Hence, problems may arise when both CAN FD protocol modules/components/elements and CAN 2.0 protocol modules/components/elements are connected to one-and-the-same CAN bus.
For these or other reasons there is a need for an improved network node, in particular, an improved network node for CAN bus systems, for an improved method of controlling a network node, and for an improved electrical or electronic device adapted to be connected to a bus, in particular, a CAN bus.